How to graph 'trapz' function

I am using a trapz function to estimate the area under a function, and am getting the answer, but I was wondering if there was any way to graph the trapeziums that the function is using to calculate the area, rather than just getting an answer down the bottom.

Side note: does anyone know why my ylim is giving an error of "Array indices must be positive integers or logical values"?

Thanks!

x=0:0.1:6;
y=(30-(exp(-2.3*x)*30))/(0.6*57400)*100-(0.015*x)
plot(x,y)
ylim ([0 0.07])
Q = trapz(x,y)

[Walter Roberson]

Check, you might have accidentally created a variable named ylim

Answer 1

[Divyajyoti Nayak]

Hey @Max Payne,

To visualize the trapeziums used for calculation by the 'trapz' function, you can make use of the 'xline' and 'area' functions like below:

x=0:0.1:6;
y=(30-(exp(-2.3*x)*30))/(0.6*57400)*100-(0.015*x)
plot(x,y)
ylim ([0 0.07])
Q = trapz(x,y)
hold on
xline(x);
a = area(x,y);
a.FaceColor = [0.3010 0.7450 0.9330];
hold off

It would look something like this: